Anion Transport in Red Blood Cells II. Kinetics of Reversible Inhibition by Nitroaromatic Sulfonic Acids

1979 ◽  
Vol 2 (2) ◽  
pp. 255-281 ◽  
Author(s):  
M. Barzilay ◽  
Z. I. Cabantchik
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Anion Transport ◽  
Sulfonic Acids ◽  
Reversible Inhibition ◽  
Kinetics Of

Kinetics of Na-Li exchange in high and low K sheep red blood cells

1989 ◽  
Vol 257 (1) ◽  
pp. C58-C64 ◽  
Author(s):  
K. H. Ryu ◽  
N. C. Adragna ◽  
P. K. Lauf
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cell Types ◽  
Sheep Red Blood Cells ◽  
High K ◽  
Ping Pong ◽  
Order Of Magnitude ◽  
Low K ◽  
Kinetics Of ◽  
System Operating

The kinetic parameters and transport mechanism of Na-Li exchange were studied in both low K (LK) and high K (HK) sheep red blood cells with cellular Na [( Na]i) and Li concentrations [( Li]i) adjusted by the nystatin technique (Nature New Biol. 244: 47-49, 1973 and J. Physiol. Lond. 283: 177-196, 1978). Maximum velocities (Vm) for Li fluxes and half-activation constants (K1/2) for Li and Na of the Na-Li exchanger were determined. The K1/2 values for both Li and Na appeared to be similar in both cell types, although they were about two to three times lower on the inside than on the outside of the membrane. Furthermore, the K1/2 values for Li were at least an order of magnitude smaller than those for Na, suggesting substantial affinity differences for these two cations. The Vm values for Li fluxes, on the other hand, appear to be lower in HK than in LK cells. When Na and Li fluxes were measured simultaneously, a trans stimulatory effect by Na on Li fluxes was observed. From measurements of Li influx at different concentrations of external Li and different [Na]i, the ratio of the apparent Vm to the apparent external Li affinity was calculated to be independent of [Na]i for both types of sheep red blood cells. Similar trans effects of external Na were observed on Li efflux at varying [Li]i. These results are expected for a system operating by a “ping-pong” mechanism.

Differentiation of Na(+)-K+ pumps of low-K+ sheep red blood cells is promoted by Lp membrane antigens

1993 ◽  
Vol 265 (1) ◽  
pp. C99-C105 ◽  
Author(s):  
Z. C. Xu ◽  
P. B. Dunham ◽  
B. Dyer ◽  
R. Blostein
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Rat Kidney ◽  
Striking Increase ◽  
Sheep Red Blood Cells ◽  
High K ◽  
Membrane Antigens ◽  
Low K ◽  
Kinetics Of

Na(+)-K+ pumps of red blood cells from sheep of the low-K+ (LK) phenotype undergo differentiation during circulation, manifested in part by a striking increase in sensitivity to inhibition by intracellular K+ (Ki). Pumps of red blood cells from sheep from the allelic phenotype, high K+ (HK), do not undergo this type of maturation. The hypothesis was tested that the Lp antigen, found on LK but not HK cells, is responsible for the maturation of LK pumps. Lp antigens have been shown to inhibit LK pumps because anti-Lp antibody stimulates the pumps by relieving inhibition by the antigen. Lp antigens were recently shown to be molecular entities separate from Na(+)-K+ pumps [Xu, Z.-C., P. Dunham, J. Munzer, J. Silvius, and R. Blostein. Am. J. Physiol. 263 (Cell Physiol. 32): C1007-C1014, 1992]. The test of the hypothesis was to modify the Lp antigens of immature LK red blood cells with two kinds of treatments, anti-Lp antibody and trypsinization (which cleaves Lp), and to observe the effects of these treatments on maturation of pumps during culture of the cells in vitro. Both of these treatments prevented the maturation of the kinetics of the pumps to the Ki-sensitive pattern, supporting the hypothesis that interaction of the pumps with Lp antigens is responsible for the maturation of the pumps. Strong supportive evidence came from experiments on Na(+)-K+ pumps from rat kidney delivered into immature LK sheep red blood cells by microsome fusion.(ABSTRACT TRUNCATED AT 250 WORDS)

K562 cell anion exchange differs markedly from that of mature red blood cells

1983 ◽  
Vol 244 (1) ◽  
pp. C68-C74 ◽  
Author(s):  
F. Y. Law ◽  
R. Steinfeld ◽  
P. A. Knauf
Keyword(s):  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Chloride Transport ◽  
K562 Cells ◽  
Band 3 ◽  
Anion Transport ◽  
Leukemic Cells ◽  
Anion Transport System

Human K562 leukemic cells exhibit several erythroid properties, including synthesis and expression of the major red blood cell sialoglycoprotein, glycophorin. This has led us to ask if these cells express a functional anion transport system analogous to that which is associated with the other major erythrocyte glycoprotein, band 3. The chloride-36 exchange flux in K562 cells is less than 0.6% of that which would be expected in mature erythrocytes under similar conditions. Unlike red blood cells, K562 cells do not exhibit a high chloride-sulfate selectivity, and various agents that inhibit red blood cell chloride exchange are all much less effective in K562 cells. On the basis of these flux measurements, K562 cells probably contain less than 600 fully functional red blood cell-like band 3 molecules per cell, in contrast to about a million molecules in the mature red blood cell. The possible-existence of greatly altered band 3 molecules with a reduced turnover rate and/or a reduced affinity for chloride and for various inhibitors is unlikely but cannot be completely excluded. Anion transport was also measured in K562 cells that had been induced to increase hemoglobin synthesis by various chemical agents. Even under these conditions, chloride fluxes indicated no substantial increase in the number of functional anion transport sites or their chloride transport rate.

STUDIES ON THE PRESERVATION OF BLOOD: III. REVERSIBLE INHIBITION OF GLYCOLYSIS IN BLOOD BY OXALATE

1954 ◽  
Vol 32 (1) ◽  
pp. 338-345
Author(s):  
Hanna M. Pappius ◽  
Orville F. Denstedt
Keyword(s):  
Red Blood Cells ◽  
Calcium Ions ◽  
Blood Cells ◽  
Reversible Inhibition ◽  
Equivalent Concentration ◽  
Glycolytic Activity ◽  
Duration Of Storage ◽  
Inhibition Of Glycolysis

Oxalate was found to inhibit glycolysis in red blood cells during storage at 5 °C. The inhibition of glycolysis in blood cells by oxalate is reversible. The glycolytic activity of the oxalated cells can be restored by washing the cells, or by precipitating the oxalate with an equivalent concentration of added calcium ions. However, with increased duration of storage prior to removal of oxalate the rate of glycolysis in the erythrocytes was found to be decreased on removal of the oxalate.

Comparison between Ca2+-induced scrambling of various fluorescently labelled lipid analogues in red blood cells

2002 ◽  
Vol 362 (3) ◽  
pp. 741-747 ◽  
Author(s):  
David W. C. DEKKERS ◽  
Paul COMFURIUS ◽  
Edouard M. BEVERS ◽  
Robert F. A. ZWAAL
Keyword(s):  
Plasma Membrane ◽  
Membrane Protein ◽  
Red Blood Cells ◽  
Phospholipase D ◽  
Blood Cells ◽  
Amino Group ◽  
Flip Flop ◽  
Putative Membrane Protein ◽  
Kinetics Of

Treatment of red blood cells with calcium and ionomycin causes activation of the lipid scramblase, a putative membrane protein catalysing flip-flop of (phospho)lipids. Various fluorescent 1-oleoyl-2-[6(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino] caproyl (C6-NBD) analogues were tested for transbilayer movement across the plasma membrane of red blood cells. Among these phospholipid analogues were phosphatidylgalactose, phosphatidylmaltose and phosphatidylmaltotriose, which were obtained from C6-NBD-phosphatidylcholine by phospholipase D-catalysed transphosphatidylation. The inward movement after the onset of scrambling was monitored by extraction of the non-internalized probe with BSA. We demonstrate that both the amino group and the size of the headgroup determine the kinetics of lipid scrambling, and that lipids with a ceramide backbone migrate much more slowly than glycerophospholipids with the same headgroup.

scholarly journals Kinetics of Cl-dependent K fluxes in hyposmotically swollen low K sheep erythrocytes.

1991 ◽  
Vol 97 (2) ◽  
pp. 173-193 ◽  
Author(s):  
E Delpire ◽  
P K Lauf
Keyword(s):  
Red Blood Cells ◽  
Kinetic Study ◽  
Kinetic Parameters ◽  
Blood Cells ◽  
Red Cells ◽  
Maximal Velocity ◽  
Temperature Dependent ◽  
Low K ◽  
Kinetics Of ◽  
External K

A detailed kinetic study of K:Cl cotransport in hyposmotically swollen low K sheep red blood cells was carried out to characterize the nature of the outwardly poised carrier. The kinetic parameters were determined from the rate of K efflux and influx under zero-K-trans conditions in red cells with cellular K altered by the nystatin method and with different extracellular K or Rb concentrations. Although apparent affinities for efflux and influx were quite similar, the maximal velocity for K efflux was approximately two times greater than for influx. Furthermore, at thermodynamic equilibrium (i.e., when the ion product of K and Cl within the cell was equal to that outside) a temperature-dependent net K efflux was observed, approaching zero only when the external product reached approximately two times the internal product. The binding order of the ions to the transporter was asymmetric, being ordered outside (Cl binding first, followed by K) and random inside. K efflux but not influx was trans-inhibited by KCl. Trans inhibition of K efflux was used to verify the order of binding outside: trans inhibition by external Cl occurred in the absence of external K, but not vice versa. Thus K:Cl cotransport is kinetically asymmetric in hyposmotically swollen low K sheep red cells.

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